At the commencement of World War I, Europeans widely believed that the war would not last long; however, contrary to that belief the war quickly reached a stalemate.To transcend the stalemate, both the Allies and the Central Powers adopted strategies of attrition. This can be seen in the growth of alliances: both sides were seemingly matched in power and size, halting the advancement of either sides' troops. Additionally, advances in technology such as U-boats, airplanes, and trenches allowed each side to better fight the war and defend their own troops. As the intensity of the war developed leaders began to obtain more power, which enabled them to have more control over their people, and draft civilians to be soldiers. WWI developed into a stalemate due to the growth of alliances, the advancement of defensive technology, and the new-found power of leaders within their own countries.